Abstract

The paternity patterns observed in decapods reflect the mating strategies and tactics employed by different species. However, these patterns may be altered by fishery management, particularly through male-biased harvesting, which affects the natural sex ratio and subsequently influences mating success and reproductive success. This study examined the reproductive strategies of the kelp crab Taliepus dentatus, revealing that, unlike other Majoidea crabs, T. dentatus demonstrates a single paternity pattern, apparently unaffected by fishing pressures. Histological analyses revealed a seminal receptacle non-compartmentalised, full of seminal material. Despite this, contrasting mating schemas in laboratory experiments (simultaneous vs sequential mating) discriminated the impacts of males and females in mating success, revealing that females were receptive approximately 50% of the time, but did not exhibit mate selection during the pre-copulatory period. Additionally, results showed that mating was mostly influenced by the presence of risk of sperm competition, as males rarely mated or displayed post copulatory guarding behaviour when other males were present. Finally, despite traits promoting multiple paternity exhibits for T. dentatus, factors such as limited natural encounters, short copulatory durations and full seminal receptacles likely contributed to the observed genetic monogamy. This research emphasises the need 1) to understand reproductive behaviours using multiple approaches (i.e. genetics, behaviour and histology) and 2) to perform contrasting mating experiments in sequential and simultaneous designs.